Three-tether axisymmetric wave energy converter: estimation of energy delivery

Abstract

There are numerous designs and concepts that have been offered to extract energy from ocean waves. A heaving buoy is distinguished as the most popular prototype which predominantly harnesses energy from the vertical motion in waves. In contrast to such devices, a three-tether wave energy converter (WEC) utilises heave, surge and pitch motion modes to increase the total power absorption of the system. The current paper investigates the performance of the three-tether WEC under irregular wave conditions considering various criteria, such as the annual mean power, characteristic mass, wetted surface and significant power take-off (PTO) force. A comprehensive analysis of buoys with different shapes, aspect ratios and masses is included in this study. Thus, the trade-off between different cost-related performance measures gives a clear comparison of this WEC against other existing prototypes.